I sowed 3 tomato types indoors and just hardening them off in my plastic greenhouse before leaving them outdoors for the summer. However I have noticed tom plants springing up all over my veg plot. I guess they have self-seeded from last year. I am suspecting that the people who owned the house last year had some toms stray over the period of the summer. I am actually happy to see them because it lets me know that end of May is the correct time to put mine outside. Happily mine are a little bigger than the outdoor germinated, but it will be interesting to compare them by the end of the summer.

Many years ago I learned that Tomato seeds can survive transportation through the human digestion system and find their way, (via the sewerage system) to the local sewage works, where solid matter is extracted before the contaminated liquids are processed.

This solid matter is exttracted and stacked in a mound and left to drain. It was observed that in a couple of weeks there were Tomato plants growing on the surface this mound!

If human waste was distributed on a garden there may well have been Tomato plants germinating and growing there in the same way.?

I have had problems of tomato blight for the past couple of years and have now lost all my tomato plants again. I planted them in the troughs or plant pots. Kept well watered. Any tips for next year please

Coralie, "blight" has become a generic term for any fungal or bacterial problem. There are actually only two Blights - Early and Late - but there are many more fungal or bacterial diseases, some of which resemble Early Blight in particular.

Can you be more specific about the symptoms - or even post a photo - so we can try to work out what the problem is? And have the plants been indoors or outdoors?

But, in general, unless you spray preventively, all you can do is try to minimise the chance of infection via housekeeping practices. I say minimise because, without preventive spraying, you can't actually stop infection. Fungal spores are invisible to the naked eye, they travel in the air, and they're everywhere. You can't avoid them.

Housekeeping practices include: keeping plants well apart to aid air circulation; judiciously removing foliage to avoid great clumps of leaves to aid air circulation; keeping the foliage as dry as possible because damp leaves are the perfect incubator for the spores. It's also a good idea to remove the lowest branches in order to maintain a gap of at least a foot between the soil and the lowest foliage. Spores can and will fall from the leaves to the soil and can be splashed back up again onto the leaves when watering. The gap helps against this.

When you say well-watered, how often were you watering? Over-watered plants - and over-fertilised plants, for that matter - can be more vulnerable to disease.

Just got back from weekend away and they were brown blotchy stems. I planted them in 12" pots and 2 plants in medium troughs. They were out door so got lots of rain on them. I did check that they were not standing in too much water. They had not flowered when I went away. Unfortuately I have just cut them up and put them in our council garden recycle bin as I did not want to put them in my compost. So I have no photo

Mmmm. About the only disease I can think of that might manifest on the stem before elsewhere is White Mould. I've only ever seen it a couple of times. It starts out as a lesion on the stem, a bit like a stain. Eventually, as the stem succumbs, it turns almost white.

EDIT. I just Googled White Mould for further info. Everyone spells it Mold. Whatever. It seems that it's most common on plants in flower and yours weren't flowering. Might be back to square one.

I don't know alot about blight but is blgiht the same for spuds as it is for toms.

There have been alot of full Smith alerts for my area of Lancashire, with 12 alerts this month alone, and alot in June and May. Depending where you live conditions have been good for blight, certainly here in the NW. There have been more alerts to date this year than for the whole of last year for my post code.

Which months are early and late blight likely to appear? I grow alot of spuds and it would be interesting to know.

Potato Blight is the same disease as Late Blight in tomatoes. The pathogen is Phytophthora infestans. In toms, it certainly manifests on the stems, but also on the leaves. That is wasn't showing on the leaves still puzzles me.

As I've posted before, it's impossible to avoid fungal spores, the pesky little things that cause these problems. They're invisible, they travel in the air, and they are everywhere.

Preventive spraying is probably the best means of preventing infection. The spray coats the leaves, creating a barrier between the fungal spores and the leaf surface, preventing the spores getting a grip and doing their damage.

Traditionally, the most common spray has been copper sulfate-based and you'll find it under various brand names in any garden centre. Technically it's organic because copper is a naturally-occurring substance. On the other hand, it's a metal, and some growers worry about a build-up of metal in the soil when the sprays drips to the ground.

Spraying is preventive, meaning it has to be undertaken before the spores arrive. It's no use spraying after the spores have arrived - that is, once fungal (or bacterial) symptoms are showing. Usually you start spraying a couple of weeks after planting out and continue to spray every week or 10 days. If it rains within that timeframe, you have to respray to recoat the leaves. Importantly, you have to spray every leaf, and both sides of every leaf.

Preventive spraying doesn't guarantee 100% that you will be fungus (or bacteria) free, but it gives you a huge head start. The only alternative to spraying is very diligent housekeeping - at least 3' between plants to aid air circulation, judicious pruning of branches and leaves to avoid great clumps of leaves which hinder air circulation, and keeping the foliage as dry as possible. Damp foliage is a fungal spore's playground. Finally, removing the lowest branches to keep a gap of at least 1' between the lowest foliage and the soil will help against the spores - that fall from the leaves to the soil - splashing back up onto the leaves when watering.

Talking of hybrids. Several years ago I was growing a mini-plum variety called Rosada in the GH and someone gave me a couple of yellow plants, probably Golden Sunrise or the like (medium fruit but average flavour), which I remember did not do very well. I kept a couple of Rosada toms for sowing the following year, and when they fruited, they came out as yellow mini-plum, very sweet and a prolific cropper, very dark leaves, which I have continued to grow every year since. Modesty forbids that I should name the variety anything other than 'those yellow things'.

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